Distributor apparatus



DISTRIBUTOR APPARATUS Filed April 6, 1959 22 I 8 J 4s E I 2 i I M 5. am; BY 0 I R. W

His Afro/nay Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Apr. 6, 1959, Ser. No. 804,265 9 Claims. (Cl. 200-30) This invention relates to distributors for motor vehicle ignition systems and more particularly to a distributor wherein means are provided for preventing the entry of dust, dirt and the like into the area where the breaker contacts are located.

In distributor apparatus it has been found desirable to ventilate the area of the distributor cap where the rotor of the distributor is located in order to remove nitrous oxide fumes that are generated as a result of arcing between the contact carried by the rotor and the contacts carried by the distributor cap. This ventilation also serves as a protection against internal condensation and sweating of the distributor cap.

The ventilating of the interior of the distributor cap is usually accomplished by forming the cap with one or more passages. These passages permit ventilation of the interior of the cap but also permit the entry of dirt, dust and the like which finds its way onto the distributor breaker contacts causing them to burn and pit with a resultant decrease in useful life of the breaker contacts and increase in maintenance costs for the machine on which the distributor is used.

It is, accordingly, an object of this invention to provide a distributor mechanism wherein the interior of the distributor cap is ventilated but wherein a dust shield is provided that prevents dust and the like from entering the area wherein the breaker contacts are located.

Still another object of this invention is to provide a dust shield for a distributor that is disposed entirely within the confines of the distributor bowl and cap and which prevents dust and the like from entering the breaker contact area. By having the dust shield positioned entirely within the confines of the distributor bowl and cap, the shield may be used with a wide variety of distributors without changing the dimensions of the distributor parts as, for example, the hold-down springs for the cap. As an example of a dust shield design wherein changing of the length of the hold-down springs for the distributor cap would be required, reference is made to the patent to Bales 2,699,345. In that patent the outer rim of the dust shield is positioned between the top edge of the distributor bowl and the lower edge of the distributor cap, thus increasing the distance between a given point on the bowl and a point on the cap as compared with a distributor where the cap is mounted directly on the bowl. This dust shield shown in Bales thus could not be used where the hold-down springs are mounted to the distributor bowl and where they have a fixed length and engage the distributor cap to hold it in contact with the bowl.

Another object of this invention is to provide a dust shield fora distributor wherein the dust shield is formed of a flexible material having a central opening that fits over a rotating part of the distributor and having an outer circumferentially extending edge that snugly engages a fixed part of the distributor.

Still another object of this invention is to provide a dust shield that is formed of a flexible plastic material that is readily cleaned after continued use within a distributor and which may be then once more inserted within a distributor to protect the breaker contacts.

A further object of this invention is to provide a dust shield for a distributor wherein the dust shield is formed of a flexible material having a central opening that fits Patented June 6, 1961 ice over a rotating part of the distributor and having an outer circumferentially extending edge that engages a fixed part of the distributor and further having a portion that engages up-turned lugs formed integrally with the breaker plate of the distributor.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein preferred embodiments of the invention are clearly shown.

In the drawings:

FIGURE 1 is a side view with palts broken away of a distributor that is fitted with the dust shield of this invention.

FIGURE 2 is a top view of the distributor illustrated in FIGURE 1 with the cap and dust shield of the distributor removed.

FIGURE 3 is a top view of the dust shield of this invention.

FIGURE 4 is a sectional view of the dust shield of FIGURE 3 taken along line 44 of FIGURE 3.

FIGURE 5 is a lower plan view of the dust shield illustrated in FIGURES 3 and 4.

Referring now to the drawings and more particularly to FIGURE 1, it is seen that a distributor is illustrated which is generally designated by reference numeral 10. The distributor has a lower cast housing generally designated by reference numeral 12 and including a bowl portion 14. A breaker plate designated by reference numeral 16 is fixed to the bowl portion 14 of the distributor by means of a plurality of threaded fasteners designated by reference numerals 18, 20, 22 and 24. The fasteners 18, 20 and 22 are threaded into up-turned lugs 26, 28 and 30 which are formed integrally with the breaker plate 16.

The breaker plate 16 carries the usual contact set designated in its entirety by reference numeral 27. This contact set is fastened to the breaker plate 16 and includes an arm 29 carrying a rubbing block 31 and a breaker contact 32. The arm 28 is pivoted to a post 35 and the breaker contact 32 cooperates with a second breaker contact 34 which is supported from a base plate portion 36 of the contact set. It will be appreciated that the contact set might take other forms and its particular construction forms no part of the present invention.

The distributor bowl 14 carries a terminal designated in its entirety by reference numeral 38 which is connected with a spring 40 that serves to bias the arm 29 to cause engagement of breaker contacts 32 and 34 and which also serves as an electrical connection for the breaker contact 32. The terminal 38 is connected with a condenser designated by reference numeral 42 by means of a lead 44. It is seen that the condenser is fixed to the breaker plate 16.

The housing 12 of the distributor rotatably supports a shaft that carries a cam designated by reference numeral 46. A suitable centrifugal advance mechanism which is responsive to speed and which is well known to those skilled in the art is positioned within the lower portion of the bowl 14 to control the positioning of cam 46 with respect to its driving shaft. The centrifugal advance mechanism is not illustrated but it could take any conventional form and might be of the type illustrated in the Bales Patent 2,699,345. The cam 46 as is well known'to those skilled in the art engages the rubbing block 31 to periodically separate contacts 32 and 34 during rotation of the cam.

The cam 46 has an upwardly extending portion designated by reference numeral 48 that supports a rotor generally designated by reference numeral 50. The rotor 50 is driven by the extending portion 48 of the cam 46 and has a contact designated by reference numeral 52 which enemas eenstana engages a fixed contact 54 connected with the center terminal of the distributor cap 56. The contact 52 is supported by a member 58 formed of spring metal material and this member is contacted by a contact member 60 which swings close to contacts 62 that are connectea with the outer terminals of the distributor cap. The rotor 50, as is clear from FIGURE 1, is press fitted onto the portion 48 of the cam member i6 so that the member 48 and the rotor 50 rotate together. The distributor cap 56 is formed of suitable moldable insulating material and has one or more openings (not shown) connecting the interior of the distributor cap with the exterior there of. These openings serve to ventilate the area of the distributor where the rotor 54) is located and serve to ventilate the area where contacts 52 and 54 are located as well as the area wherein the member 69 swings close to the contacts 62.

It is apparent from FIGURE 1 that the ventilation of the area wherein the rotor 50 is located would normally communicate with the area wherein the breaker contacts 32 and 34 were located. It is seen, however, that an imperforate dust shield generally designated by reference numeral 70 is provided which forms a barrier between the 'area that contains the breaker contacts 32 and 3d and the area which contains the rotor 9. The dust shield, as is better illustrated in FIGURES 3, 4 and 5, is generally dome-shaped having a central opening defined by a hub portion 72. The hub portion is slit at a plurality of circumferentially spaced points designated by reference numeral 74. The dust shield 70 has an outer circumferentially extending edge portion 76 and the dome-shaped portion 78. The dome-shaped portion '78 has a pair of ribs 80 and 82 extending upwardly from the top surface thereof. A plurality of ribs designated by reference numeral 84 are also provided which interconnect the peripheral edge 76 and the portion of the dust shield designated by reference numeral 86. It is seen that these ribs 8 extend from the lower part or underside of the dome-shaped portion 78 of the dust shield. The ribs 80 and 82 and the ribs 84 all serve to enhance the lateral stability of the dust shield while the ribs 80 and 82 also serve as tab members that may be easily grasped when inserting the dust shield or withdrawing it from the distributor.

The dust shield 70 is formed of a flexible plastic material such as polyethylene, nylon, polypropylene and the like. By forming the dust shield of plastic material having a certain amount of flexibility or elasticity the outer edge 76 always makes good contact with the bowl portion of the distributor and the hub portion 72 makes good contact with the distributor rotor without regard to variance in manufacturing tolerances of the distributor and without regard to the finish of the bowl portion of the distributor. The dust shield when "fabricated of plastic material also may be readily cleaned and then used again and has good wearing qualities.

It can be seen from FIGURE 1 that the dust shield 76 will positively prevent dust from entering the area where the breaker contacts 32 and 3 are located. It is also seen that the hub portion 72 of the dust shield 7G snugly engages the portion 51 of the rotor 50. In addition, it is observed that the peripheral edge 76 of the dust shield tightly engages the inner wall of the bowl portion 1a of the housing 12. The peripheral edge 76 also engages the top edges of the up-turned lugs 26, 28 and 30 as is clearly apparent from the drawings. With this arrangement, a tight seal is provided between the dust shield 70 and the bowl portion 14 of the lower housing and between the dust shield and the rotor 59. It will, of course, be appreciated that the rotor 50 rotates with respect to the dust shield 70 with the hub portion 72 of the dust shield contacting the rotor during its rotation.

1 While the embodiments of the invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

'1. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a base portion and a cap carrying a plurality of fixed electrical contacts, said cap resting on said base portion, a rotor located within said cap carrying an electrical contact that cooperates with said fixed contacts, a pair of breaker contacts, and a dust shield formed of flexible plastic material capable of radial deflection having a portion thereof closely engaging said rotor and having a peripheral edge engaging said base portion, said dust shield being located between the area containing said rotor and the area containing said breaker contacts and contacting said base portion only along its peripheral edge.

2. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a base portion and a cap carried by said base portion having a plurality of electrical contacts, a breaker plate, a pair of breaker contacts supported by said breaker plate, a rotatable cam member cooperating with said breaker contacts, a rotor member rotatable with said cam member having a contact cooperating with the contacts carried by said cap, and a flexible imperforate dust shield capable of radial deflection having a hub portion snugly engaging a rotatable part of the distributor and having an outer circumferentially extending edge engaging a fixed part of the distributor, said dust shield separating the area containing said breaker contacts from the area containing said rotor and contacting the said fixed part of the distributor only along its peripheral edge.

3. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a lower bowl portion and a cap engaging said lower bowl portion and extending upwardly therefrom, said cap and said bowl portion defining a chamher and said cap carrying a plurality of fixed electrical contacts, a rotatable cam adapted to be driven by said engine, a pair of breaker contacts cooperating with said rotatable cam, a rotor member driven by said rotatable cam having a contact that cooperates with said fixed contacts of said cap, and means separating said chamber into two separate chambers comprising a flexible dust shield capa ble of radial deflection having an outer circumferentially extending edge engaging an inner wall of said bowl portion and having a central hub portion snugly engaging said rotor, said two chambers containing respectively the breaker contacts and the contact carried by said rotor that cooperates with said fixed contacts of the cap, said dust shield contacting the inner wall of said bowl portion only along its circumferentially extending edge.

4. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a rotatable part and including a base portion formed substantially in the shape of a bowl, a hollow distributor cap engaging said base'portion, said base portion and said distributor cap defining a chamber having an inner circumferentially extending wall, means dividing said chamber into two separate chambers including a flexible dust shield capable of radial deflection having an outer circumferentially extending edge engaging said circumferentially extending wall and having a central hub portion snugly engaging said rotatable part of said distributor, a rotor member carrying an electrical contact that cooperates With the fixed contacts of the cap disposed within one of said chambers, and a pair of breaker contacts disposed within the other of said chambers, said dust shield contacting said circumferentially extending wall only along its outer circumferentially extending edge.

5. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a lower base portion formed in the shape of a bowl, a breaker plate having a plurality of up-turned lugs located Within said base portion, a'contact set including a pair of breaker contacts supported by said breaker plate, a rotatable cam that is adapted to be driven by said engine cooperating with said breaker contacts, a distributor cap supported by said lower base portion hav ing a plurality of fixed contacts, a rotor member rotatable with said cam member having a contact that cooperates with said fixed contacts, and means forming an imperforate barrier between the area containing said breaker contacts and the area containing said rotor, said last-named means comprising a flexible dust shield capable of radial deflection having a hub portion engaging said rotor member and having an outer circumferentially extending edge engaging an inner surface of said base member and engaging the top edges of said up-turned lugs, said dust shield engaging the inner surface of said base member only along its circumferentially extending edge.

6. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a rotatable part and including a base portion formed substantially in the shape of a bowl, a hollow distributor cap engaging said base portion, said base portion and said distributor cap defining a chamber having an inner circumferentially extending wall, means dividing said chamber into two separate chambers including a flexible dust shield having an outer circumferentially extending edge engaging said circumferentially extending Wall and having a central hub portion engaging said rotatable part of said distributor, a rotor member carrying an electrical contact that cooperates with the fixed contacts of the cap disposed within one of said chambers, and a pair of breaker contacts disposed within the other of said chambers, said dust shield being formed with a plurality of radially extending ribs that serves to enhance the lateral stability of the dust shield.

7. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a rotatable part and including a base portion formed substantially in the shape of a bowl, a hollow distributor cap engaging said base portion, said base portion and said distributor cap defining a chamber having an inner circumferentially extending wall, means dividing said chamber into two separate chambers including a flexible dust shield having an outer circumferentially extending edge engaging said circumferentially extending wall and having a central hub portion engaging said rotatable part of said distributor, a rotor member carrying an electrical contact that cooperates with the fixed contacts of the cap disposed within one of said chambers, and av pair of breaker contacts disposed Within the other of said chambers, said dust shield being formed with a plurality of radially extending ribs at least one of which extends upwardly from the dust shield to provide a gripping surface.

8. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a rotatable part and including a base portion formed substantially in the shape of a bowl, a hollow distributor cap engaging said base portion, said base portion and said distributor cap defining a chamber having an inner circumferentially extending wall, means dividing said chamber into two separate chambers incluing a flexible dust shield having an outer circumferentially extending edge engaging said circumferentially extending Wall and having a central hub portion engaging said rotatable part of said distributor, a rotor member carrying an electrical contact that cooperates with the fixed contacts of the cap disposed within one of said chambers, and a pair of breaker contacts disposed within the other of said chamhere, said dust shield being substantially dome-shaped and having a plurality of radially extending ribs that enhance the lateral stability of the dust shield.

9. In a distributor for the ignition system of an internal combustion engine, the combination comprising; a distributor having a rotatable part and including a base memher, a hollow distributor cap engaging said base member, said member and said distributor cap defining a chamber having an inner circumferentially extending, Wall, means dividing said chamber into two separate chambers in cluding a flexible dust shield capable of radial deflection having an outer circumferentially extending edge engaging said circumferentially extending wall and having a central hub portion snugly engaging said rotatable part of said distributor, said dust shield having a plurality of radially extending ribs that serve to enhance the lateral stability of the dust shield, a rotor member carrying an electrical contact that cooperates with the fixed contacts of the cap disposed within one of said chambers, and a pair of breaker contacts disposed within the other of said chambers.

References Cited in the file of this patent UNITED STATES PATENTS 1,903,135 Rees Mar. 28, 1933 2,357,973 Robbins Sept. 12, 1944 2,657,556 Elliott Nov. 3, 1953 2,718,564 Collins et a1 Sept. 20, 1955 2,773,140 Guernsey et al Dec. 4, 1956 2,791,649 Baker May 7, 1957 2,899,516 Smith Aug. 11, 1959 FOREIGN PATENTS 518,252 Germany Feb. 13, 1931 970,015 Germany Aug. 14, 1958 

